Research On Key Technologies Of 3D Measurement Of Structured Light Field

With the development and advancement of science and technology,threedimensional stereoscopic vision has occupied an increasingly important position in our lives,so 3D measurement technology has also received more and more attention.From the initial contact three-dimensional measurement method to the numerous non-contact three-dimensional measurement technology that has evolved from the beginning,it can be seen that the three-dimensional measurement technology is developing in the direction of fast,convenient,high precision and high stability.According to the principle of light field imaging,it records the position and direction information of light in space.Different from other measurement techniques,it promotes the traditional way of recovering three-dimensional information from two-dimensional data to the height of recovering three-dimensional information from four-dimensional data.Become a research hotspot in the field of 3D measurement.Therefore,this paper studies and analyzes some methods based on threedimensional measurement technology of light field imaging.At the same time,combined with the advantages of the existing traditional measurement methods,a measurement system that combines the advantages of both is proposed,and then based on the light field data.Two different acquisition methods were tested and analyzed.The main research contents are as follows:First,the development and research status of 3D measurement technology is introduced.The theory of fringe projection technology is expounded,including imaging model of camera,phase shift method and principle of depth estimation.Secondly,the concept,development and research status of light field imaging technology are briefly described,and many key technologies in the measurement principle,including parametric representation of light field,acquisition method and depth estimation,are analyzed.Third,in the traditional three-dimensional measurement method,the surface of the measured object has three-dimensional data that is difficult to measure,such as occlusion,shadow,highlight,and the like.Aiming at this situation,a flexible threedimensional measurement system based on structured light markers is proposed.The stripe projection technique is used to mark the phase values of the object,and the light field data is collected by a camera array having high resolution and no crosstalk between images at different viewing angles,and the depth can be quickly obtained by using the polar plane analysis method.Identify and find the corresponding phase values of the same point at different viewing angles.Achieve high precision,high stability,and more complete 3D measurement of the object surface.Fourth,the system structure of the camera array is too large,and the measurement process is cumbersome.Therefore,a three-dimensional measurement system based on micro-lens array and an auxiliary system for system calibration were built to measure the proposed method.The micro-lens array can acquire sub-images of objects imaged at different viewing angles by one shot.By encoding the phase marks of the stripe,the light information of the depth information in the four-dimensional light field data can be quickly and accurately determined,and the reconstruction result of the auxiliary system is utilized.System parameters and 3D measurement results are calculated and verified to achieve the measurement of the complete surface of the object.